How to Force Camassia and Fritillaria Bulbs for Winter Blooms, According to Martha

During the cold New York winters, Martha uses a gardening technique called forcing to bring the spring blooms into her greenhouse. She uses this technique every year for amaryllis bulbs, but this year, she is also using the technique on her checkered Fritillaria meleagris and blue star-shaped Camassia, which she grows abundantly outdoors in the warmer months.

Martha's method for forcing the bulbs begins with picking up three pots worth of bulbs from a local wholesale flower merchant. To accommodate the bulbs, Martha and her head gardener, Ryan McCallister, use wide-mouthed planters and fill them with Miracle-Gro Moisture Control Potting Mix, according to Martha's recent blog post. She also suggests adding a mix of Osmocote fertilizer for a slow release of nutrients in the following months after planting.

The forcing technique is similar for both types of bulbs. To begin, plant the bulbs and gently push each down into the soil, ensuring the bulb roots point downward. Martha writes: "The bulbs can be placed close together. They will hold one another upright and show beautifully in maximum blooms." She adds, "Any bulbs used for forcing should be dense and heavy and free from mold, mildew, discoloration, or a peeling outer shell."

After you secure the bulbs in the soil, cover them with another layer of potting mix so you fill it just below the brim of the pot. Then layer pea stone to cover the soil to help bolster the stems as they grow.

The forcing process for the Frillaria bulbs differs slightly from the Camassia because you need to water them once you place the final layer of soil on top of the bulbs. After watering, find a windowsill indoors where the planter can soak up sun and dry before you place pea stone on top of the soil.

Martha says the forcing process takes six to eight weeks—and sometimes even up to 13 weeks—before the bulbs begin to flower. The bright-colored blooms will be well worth the wait and a beautiful addition to your home during the cold and gloomy months.